Exemplary embodiments of the inventive concept relate to an image sensor, and more particularly, to an image sensor for increasing the sensitivity and transmittance of a blue color filter in an image processing system, as well as reducing cross-talk.
An image sensor is a device that converts an optical image into an electrical signal. The image sensor is used in digital cameras and various image processing devices such as a digital camera. Image sensors are divided into charged coupled device (CCD) image sensors and complementary metal-oxide-semiconductor (CMOS) image sensors.
An image sensor includes a plurality of pixels arranged in a matrix. Each of the pixels includes a photoelectric conversion element that converts incident light into electrical signals and a plurality of transistors to read out the electrical signals from the photoelectric conversion element
A color image sensor includes a plurality of color filters, e.g., a red color filter, a green color filter, and a blue color filter. Each of the color filters is included in a corresponding pixel. A color filter transmits wavelengths in a certain color range to a photoelectric conversion element included in a corresponding pixel. However, since the color filter itself absorbs a lot of wavelengths in the color range, the photoelectric conversion element cannot satisfactorily and effectively use the wavelengths that have passed through the color filter. In this circumstance, the sensitivity of an image sensor may be reduced.